Just about every new turbine powered a/c being delivered today from a King Air 90 to a GVSP to an ERJ to the 747 400 has an FMS/GPS or FMS/INS, and has had for many years.

For the dispatch operations of a major airline, the effect is huge. The a/c is smarter, so dispatch ops are simplified due to point to point capability. In some cases, a greater variety of approaches is available, which increases access to airports that have less than stellar radar coverage, either as an alternate or primary airport. Accurate fuel burn/step climb/enroute wind data enables "What if" type of planning, which pays directly to revenue enhancement. Typically the graphics driven by the FMC make the a/c simpler to fly, so human factors issues are large...

I don't think one could find an airline that didn't spec an FMS of some kind on an airliner...

Really, it's just an FMS that enabled the F/A 18 to become what it is...but I digress.

I think you're mistaking other aircraft systems with an FMS in the case of the F/A 18 or the maintenance function you speak of.

Flight computers make unstable aircraft like the F/A 18 fly. CAMS systems provide integrated maintenance systems that can be merely displayed on an FMS.

And you're right...many new aircraft are spec'd with an FMS. But certainly not ALL commercial airliners. I know of many 737/727/DC-9 aircraft which are still quite abundant (and the MAJORITY) of Kingairs and SAAB 340s and EMB 120s and Dash 8s that do NOT have an FMS installed.

Of course there are exceptions, but remember what the original post said:

"Does every airliner must have a navigation system like INS FMC, or FMS?
thanks"

The older 737s, the 727s, DC9s and EMB120s may account for maybe 20% of the current airliner fleet in the US, and are being parked on a daily basis...

With regard to the F18, a computer is a computer whether one calls it an FMS or an APG xx...(yeah, yeah, an integrated radar). The F/A 18 has "Flip of the switch" mission capability b/c of its FMS that integrates the air to air functions of the radar with ground map mode, and many other functions. Active flight control or dynamic instability is only a small piece of the pie.

What was stated was that just about every commercial a/c does NOT have an FMS. I disagree with that statement, and went on to clarify it by stating that it's difficult to find an new 121 a/c today w/o one, and the reasons why they are desireable.

Your statement questioned their benefit for domestic use on the airways; if your point was valid, dropping the FMS out of commercial a/c would make them cheaper - and a lot less profitable for the reasons I mentioned. Every hear of an airline ordering a new a/c w/o FMS?

To go along with what "Essential" said, the FMS is one of the few pieces of equipment on an airplane that literally pays for itself many times over. The fuel savings accrued from direct routings is significant and amounts to a lot of $$$. From a situational awareness point of view they are about as good as it gets - PROVIDED the crew is proberly trained - watching your progress on a map displayed on one of the MFDs along with the other traffic and weather sure can make life easier. Additionally the flexibility and workload reduction that they provide when it comes to instrument approaches is another reason that they are pretty much standard equipment in all new turbine-powered aircraft, not just airliners.

Yes I agree that an FMS is useful. I just disagree that "ALL" commercial aircraft have one.

As far as the "maintenance" page you speak of, depending on the FMS this can represent 2 different things:

1) FMS maintenance pages that allow for FMS configuration programming and maintenance to the FMS

2) FMS CDU is used by the CAIMS system to display maintenance information. The FMS is just acting as a display. FMSs are convenient that way. They can be used to display TAWS terrain, Video, AFIS information (and control) etc. If you don't have an FMS you can use other displays.

I flew aboard an ex-QQ MD-80 series aircraft with American and the pilot said the aircraft had nothing more sophisticated than navigation radios. He explained that since the plane's service is strictly limited to domestic flights (west coast primarily), there really wasn't a need for an INS/IRS/GPS system.

I left out many like the 172 that arguably are mostly owned privately or spend their "commercial" life in flying schools.

Here's some interesting facts: There were about as many Navajos produced as there are 737s (all variants). There are more Cessna 402s in the world than there are 767s. (All variants) There are roughly 4 times the amount of Bell 206's in the world than Airbus A320s.

Not all "commercial" aircraft are modern airliners and "most" of the "commercial" aircraft in the world are not fitted with INS, FMC or FMS.

I could agree that most "modern" airliners and business jets are fitted with an FMC or FMS? How's that?

So some operators decided not to spec an FMS, and that means that MOST commercial A/C don't have an FMS? No way.

That's a real contemporary list of a/c ya got there.

All the piston equpiment - I heard FLexjet is buying 300 Cherokee 6s, slightly used of course. Seems everyone at Van Nuys and Dupage think about a '64 model Aztec is the only way to go cross country. Some outfit flying Trilanders in Puerto Rico doesn't exactly account for a large percentage of commercial aviation.

HHmmm... I haven't see a Shorts in operation in the US in a while...I'm sure they're 2 or 3 though. Same w/ the EMB110 and the CASA. Didn't Airtran start up with YS11s? Maybe that was JetBlue...no, no...they're flying DC3s and C46s.

And don't tell anyone, but I got a GREAT price on 20
HS-748s, and am planning on getting them certified with HUDs so I can run Horizon out of business.

Get real - most commercial a/c DO have an FMS. But I guess Jetguy is blowin smoke too...

Do yourself a favor and check out the pictures of aircraft on Airliners.net.

Then maybe you'll realize that the world doesn't stop at the US border. There are several of the aircraft types you questioned in commercial operation in the world.

Where I live there are several EMB110s, HS-748s, Navajos, KingAirs and even a couple of C-46's and DC-3s that operate commercially. Throw in several 737-200s and F-28s. Round that off with lots and lots of piston Cessnas. Travelaires, Barons, Metros.....SAAB 340s (without FMS/FMS), Caravans etc.

Don't underestimate the numbers of these aircraft. They represent a significant portion of the world commerical fleet.

25 EssentialPowr
: Good point... "Several Emb110s, HS 748s and even a couple of C-46s where you live" certainly sounds representative of the commercial a/c fleet as comm